1. Field of the Invention
The present invention relates to a method for creating 3-D curved surface by using corresponding curves in a plurality of images, and more particularly, to a method for creating 3-D curved surface by using corresponding curves in a plurality of images, which creates a curved surface model in non-uniform rational b-splines (NURBS) by obtaining more than two object images, designating corresponding curve through a convenient curve designation, and restoring 3-D information through a convenient operation of a user to model a complex curved surface object.
2. Description of the Related Art
To extract 3-D information from images, provided is a conventional technique such as a shape-from-stereo technique, a shape-from-multiple views technique, a shape-from-motion technique, etc. The shape-from-stereo automatically or manually searches correspondence between images of characteristic points in each image, and calculates distance from a camera to a 3-D point by trigonometry that utilizes calibration information of each camera.
In the shape-from-multiple views, a shape-from silhouette technique, a voxel coloring technique, and a space carving technique have been developed. The shape-from silhouette technique cuts down space formed of voxel by using silhouette information with respect to an object image having a distinguishable background and object. The voxel coloring technique determines whether an object is formed of voxel or not by checking color correspondence when a specific voxel is projected as an image. The space carving technique generalizes the shape-from silhouette technique and the voxel coloring technique.
The shape-from-motion technique traces specific points from a continuous moving image in frames, and then restores 3-D information by performing cameral self-calibration with the specific points.
To perform these techniques, camera calibration needs to be accurate and correspondence between images in specific points needs to be accurately obtained.
In most of cases, due to a camera calibration error, a correspondence error in specific points, and a 3-D information error restored by form concavity, it is difficult to create accurate a 3-D model. Additionally, since the 3-D information created by the result of these techniques is point information, additional post-processing algorithm is required to create a soft 3-D curved surface that constitutes the surface of an actual object by using the point information.